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The present paper reports a remote carbon‐to‐carbon boryl migration via an intramolecular 1,4‐B/Cu shift, which establishes an in situ stereospecific electrophilic trap on the alkene moiety. The synthetic application is developed to prepare functionalized cyclopentenes by means of a palladium‐catalyzed regioselective intramolecular coupling that completes a strategic cyclopropanation and generates valuable structural bicyclic systems. The mechanism is characterized by DFT (density functional theory) calculations which showed that the 1,4‐migration proceeds through an intramolecular, nucleophilic attack of the copper‐alkyl moiety on the boron atom bonded to the C(sp2), leading to a 5‐membered boracycle structure. The computation of the 1,3‐ and 1,4‐B/Cu shifts is also compared as is the impact of the endo‐ or exocyclic alkene on the reaction kinetics. [ABSTRACT FROM AUTHOR]

The capacity to manipulate magnetization in 2D dilute magnetic semiconductors (2D‐DMSs) using light, specifically in magnetically doped transition metal dichalcogenide (TMD) monolayers (M‐doped TX2, where M = V, Fe, and Cr; T = W, Mo; X = S, Se, and Te), may lead to innovative applications in spintronics, spin‐caloritronics, valleytronics, and quantum computation. This Perspective paper explores the mediation of magnetization by light under ambient conditions in 2D‐TMD DMSs and heterostructures. By combining magneto‐LC resonance (MLCR) experiments with density functional theory (DFT) calculations, we show that the magnetization can be enhanced using light in V‐doped TMD monolayers (e.g., V‐WS2, V‐WSe2). This phenomenon is attributed to excess holes in the conduction and valence bands, and carriers trapped in magnetic doping states, mediating the magnetization of the semiconducting layer. In 2D‐TMD heterostructures (VSe2/WS2, VSe2/MoS2), the significance of proximity, charge‐transfer, and confinement effects in amplifying light‐mediated magnetism is demonstrated. We attributed this to photon absorption at the TMD layer that generates electron–hole pairs mediating the magnetization of the heterostructure. These findings will encourage further research in the field of 2D magnetism and establish a novel design of 2D‐TMDs and heterostructures with optically tunable magnetic functionalities, paving the way for next‐generation magneto‐optic nanodevices. [ABSTRACT FROM AUTHOR]

Magnesium (Mg)‐ion batteries with low cost and good safety characteristics has attracted a great deal of attention recently. However, the high polarity and the slow diffusion of Mg2+ in the cathode material limit the development of practical Mg cathode materials. In this paper, an anion‐rich electrode material, NiS2, and its composite with Ni‐based carbon nanotubes (NiS2/NCNTs) are explored as the cathode materials for Mg‐ion batteries. These NiS2/NCNTs with excellent Mg2+ storage property is synthesized by a simple in situ growth of NiS2 nanoparticles on NCNTs. NiS2 with both a large regular cavity structure and abundant sulfur‐sulfur (SS) bonds with high electronegativity can provide a large number of active sites and unobstructed transport paths for the insertion–disinsertion of Mg2+. With the aid of 3D NCNTs skeleton as the transport channel of the electron, the NiS2/NCNTs exhibit a high capacity of 244.5 mAh g−1 at 50 mA g−1 and an outstanding rate performance (94.7 mAh g−1 at 1000 mA g−1). It achieves capacitance retention of 58% after 2000 cycles at 200 mA g−1. Through theoretical density functional theory (DFT) calculations and a series of systematic ex situ characterizations, the magnesiation/demagnesiation mechanisms of NiS2 and NiS2/NCNTs and are elucidated for fundamental understanding. [ABSTRACT FROM AUTHOR]

This paper shows how terahertz light can drive ultrafast topological phase transitions in monolayer transition metal dichalcogenides (TMDs). The phase transition is induced by the light interaction with both electron and phonon subsystems in the material. The mechanism of such a phase transition is formulated by thermodynamics theory: the Gibbs free energy landscape can be effectively modulated under light, and the relative stability between different (meta‐)stable phases can be switched. This mechanism is applied to TMDs and reversible phase transitions between the topologically trivial 2H and nontrivial 1T′ phases are predicted, providing appropriate light frequency, polarization, and intensity are applied. The large energy barrier on the martensitic transformation path can be significantly reduced, yielding a small energy barrier phase transition with fast kinetics. Compared with other phase transition schemes, light illumination has great advantages, such as its non‐contact nature and easy tunability. The reversible topological phase transition can be applicable in high‐resolution fast data storage and in‐memory computing devices. [ABSTRACT FROM AUTHOR]

Doping perovskite oxide with different cations is used to improve its electro‐catalytic performance for various energy and environment devices. In this work, an activated lattice oxygen activity in Pr0.4Sr0.6CoxFe0.9−xNb0.1O3−δ (PSCxFN, x = 0, 0.2, 0.7) thin film model system by B‐site cation doping is reported. As Co doping level increases, PSCxFN thin films exhibit higher concentration of oxygen vacancies (Vo••) as revealed by X‐ray diffraction and synchrotron‐based X‐ray photoelectron spectroscopy. Density functional theory calculation results suggest that Co doping leads to more distortion in FeO octahedra and weaker metaloxygen bonds caused by the increase of antibonding state, thereby lowering Vo•• formation energy. As a consequence, PSCxFN thin film with higher Co‐doping level presents larger amount of exsolved particles on the surface. Both the facilitated Vo•• formation and B‐site cation exsolution lead to the enhanced hydrogen oxidation reaction (HOR) activity. Excessive Co doping until 70%, nevertheless, results in partial decomposition of thin film and degrades the stability. Pr0.4Sr0.6(Co0.2Fe0.7Nb0.1)O3 with moderate Co doping level displays both good HOR activity and stability. This work clarifies the critical role of B‐site cation doping in determining the Vo•• formation process, the surface activity, and structure stability of perovskite oxides. [ABSTRACT FROM AUTHOR]